make that amend, which we've now done, 27 times. >> when you look at founding documents of our country, they are elastic, they are meant boo toe pulled and bent in different directions as each era dictates. >> reporter: so, today, right now, when we argue whether it's consnstutional to send drones over libya. for the government to make immigrants carry i.d. cards. those are only possible in a a sense because there is a constitution, as the framers wrote in its very first paragraph, they wanted to secure the blessings of liberty, for our posterity, that's us, we, the people. we're still here, thanks to them and this piece of paper. for "this week" i'm john donvan in washington. >> so, as just seen, now more than ever, the constitution is at the very heart of the political debate these day, congress is now requiring that every piece of legislation come accompanied by the constitutional justification.